

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0,user-scalable=no">
    <title>Document</title>
   <!-- 官网或其他网站 -->
   <!-- <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.css" 
   type="text/css" rel="stylesheet" />  -->
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   <!-- 本地 -->
   <link href="../static/bootstrap-3.4.1/dist/css/bootstrap.css" 
   type="text/css" rel="stylesheet" /> 
<style> 
 
.h1{
       color: red;
} /**/
</style>
</head>

<body>
    <!-- html原始的效果 html规定的样式，浏览器给出默认这实现这个样式 -->
    <h1>66</h1> 
    666666666666
    <div>777777</div>
    <h1>777777</h1>

    <hr/>
    <div class="h1">8888</div>
</body>

</html>